Stems with 40-100 prickles per cm². Leaf blades: surfaces essentially unarmed between veins, abaxial surface sparingly prickly on main veins, adaxial surface unarmed or very sparingly prickly on veins. Capsules moderately short-prickly as well as long-prickly, longest prickles 8-12 mm. Flowering spring-summer; fruiting summer-fall. Arid slopes and valleys; 600-1500 m; N.Mex., Tex.